Source:http://linkedlifedata.com/resource/pubmed/id/17596298
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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
3
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| pubmed:dateCreated |
2007-9-12
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| pubmed:abstractText |
Using the human mammary epithelial cell line MCF-7, we have investigated volume-activated changes in response to hyposmotic stress. Switching MCF-7 cells from an isosmotic to a hyposmotic solution resulted in an initial cell swelling response, followed by a regulatory volume decrease (RVD). This RVD response was inhibited by the nonselective K(+) channel inhibitors Ba(2+), quinine, and tetraethylammonium chloride, implicating K(+) channel activity in this volume-regulatory mechanism. Additional studies using chromonol 293B and XE991 as inhibitors of the KCNQ1 K(+) channel, and also a dominant-negative NH(2)-terminal truncated KCNQ1 isoform, showed complete abolition of the RVD response, suggesting that KCNQ1 plays an important role in regulation of cell volume in MCF-7 cells. We additionally confirmed that KCNQ1 mRNA and protein is expressed in MCF-7 cells, and that, when these cells are cultured as a polarized monolayer, KCNQ1 is located exclusively at the apical membrane. Whole cell patch-clamp recordings from MCF-7 cells revealed a small 293B-sensitive current under hyposmotic, but not isosmotic conditions, while recordings from mammalian cells heterologously expressing KCNQ1 alone or KCNQ1 with the accessory subunit KCNE3 reveal a volume-sensitive K(+) current, inhibited by 293B. These data suggest that KCNQ1 may play important physiological roles in the mammary epithelium, regulating cell volume and potentially mediating transepithelial K(+) secretion.
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| pubmed:language |
eng
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| pubmed:journal | |
| pubmed:citationSubset |
IM
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| pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Hypotonic Solutions,
http://linkedlifedata.com/resource/pubmed/chemical/Isotonic Solutions,
http://linkedlifedata.com/resource/pubmed/chemical/KCNE3 protein, human,
http://linkedlifedata.com/resource/pubmed/chemical/KCNQ1 Potassium Channel,
http://linkedlifedata.com/resource/pubmed/chemical/KCNQ1 protein, human,
http://linkedlifedata.com/resource/pubmed/chemical/Potassium,
http://linkedlifedata.com/resource/pubmed/chemical/Potassium Channels, Voltage-Gated,
http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger
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| pubmed:status |
MEDLINE
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| pubmed:month |
Sep
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| pubmed:issn |
0363-6143
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| pubmed:author | |
| pubmed:issnType |
Print
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| pubmed:volume |
293
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| pubmed:owner |
NLM
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| pubmed:authorsComplete |
Y
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| pubmed:pagination |
C1010-9
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| pubmed:meshHeading |
pubmed-meshheading:17596298-Adenocarcinoma,
pubmed-meshheading:17596298-Breast Neoplasms,
pubmed-meshheading:17596298-Cell Line, Tumor,
pubmed-meshheading:17596298-Cell Polarity,
pubmed-meshheading:17596298-Epithelial Cells,
pubmed-meshheading:17596298-Extracellular Fluid,
pubmed-meshheading:17596298-Humans,
pubmed-meshheading:17596298-Hypotonic Solutions,
pubmed-meshheading:17596298-Isotonic Solutions,
pubmed-meshheading:17596298-KCNQ1 Potassium Channel,
pubmed-meshheading:17596298-Mammary Glands, Human,
pubmed-meshheading:17596298-Membrane Potentials,
pubmed-meshheading:17596298-Mutagenesis, Site-Directed,
pubmed-meshheading:17596298-Osmotic Pressure,
pubmed-meshheading:17596298-Potassium,
pubmed-meshheading:17596298-Potassium Channels, Voltage-Gated,
pubmed-meshheading:17596298-RNA, Messenger,
pubmed-meshheading:17596298-Water-Electrolyte Balance
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| pubmed:year |
2007
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| pubmed:articleTitle |
Contribution of KCNQ1 to the regulatory volume decrease in the human mammary epithelial cell line MCF-7.
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| pubmed:affiliation |
Dept. of Physiology and Biophysics, Dalhousie Univ., Halifax, Nova Scotia B3H 1X5, Canada. elizabeth.cowley@dal.ca).
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| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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